About: http://webisa.webdatacommons.org/425770407

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	The acid test someone mentioned works, though vinegar is a fairly mild acid and a better would be the regent #2 from the API nitrate test kit; but if vinegar fizzes, it is calcareous.
http://www.w3.org/ns/prov#wasQuotedFrom	tropicalfishkeeping.com